Choline inhibits the gelification of highly concentrated orthosilicic acid (OSA) and oligomers at very low pH so that stable solutions ready for use can be prepared which are bioavailable for man, plant and animal. Polymers of OSA are huge molecules (also called macromolecules) formed from hundred or thousands of units called monomers (OSA) whereas oligomers are molecules of intermediate size—much larger than monomers but less than macromolecules (Brinker CJ et al, Sol-Gel Science, The Physics and Chemistry of Sol-Gel processing, Academic Press, Boston, p. 5)
Choline plays also an important role in fat metabolism of humans and animals and is part of all kind of living cells in the form of a phosphatidyl choline, an important phospholipid of our cell membrane. Humans cynthesize choline from glycine, but this synthesis seems not to be enough for good health conditions all over the years. It is also present as acetylcholine, an important neurotransmitter. It is known as a vitamin B4. Moreover choline is an osmolyte and precursor of another important osmolyte, betaine. It is used as a food supplement in conditions as alcoholism, Alzheimer disease, angina pectoris, arteriosclerosis, asthma, cirrhosis of the liver, cystinuria, depression, diabetes, eczema, fatty liver, hair and nail problems, hepatitis, high cholesterol, hypertension, kidney liver damage, MS, etc. It is also related with the action of folate.
Although most people take enough through their food (as lecithin), there are reports that most people lack choline. A low intake of folate could be the reason for the shortness of choline in the body. Recent preliminary studies in rats show that choline could be involved in the osteogenesis and bone remodeling (Gugulielmottic et al., IADR 80 th General Session, 2002) The daily intake of choline is estimated at 200-1000 mg/day. The national academy of sciences classified choline in 1998 as an essential nutrient (Institute of Medicine, Food and Nutrition Board, Dietary reference Intake, 1998, 390-422) after a study (Zeisel, 2000, Nutrition, 16, 669-671) showing that volunteers on a choline deficient diet were not able to produce enough choline. It was observed that choline deficiency causes histopathological changes in the cartilage similar to those found in manganese deficient chicks, i.e. poor developments of bones, joints and cartilage. The inter-relationship of choline, methionine and betaine and their differences was recently reviewed (Workel et al., 1998, World Poultry, 14, 1998). Choline alone is needed as essential constituent for phospholipids, normal maturation of cartilage matrix of bone, and prevention of perosis in broilers.
The role of silicon in plants, animals and humans is well documented. It is known that orthosilicic acid is the biological active molecule and also that silicon in food and drinking water has to be processed into orthosilicic acid to be absorbed and transported in the organism. Orthosilicic acid, a very weak acid, is not very stable at all pH lower than 9.5 and quickly precipitates or forms sols or gels which are not so bioavailable for the organisms. It is therefore very difficult to prepare highly concentrated (>0.5% silicon) solutions of orthosilicic acid and oligomers convenient as stock solution for the different organisms.
In earlier patent applications (WO 95/21124) methods were described to prepare highly concentrated solutions, stable in time at different temperatures. These stock solutions are prepared, according to the preparation example, by hydrolysing a silicon source in an acid choline solution. Thereafter, the solution is neutralized by adding sodium hydroxide to a pH of 1.3 and purified over active carbon. The precipitate is filtered off and the solution is distilled under vacuum to obtain a preparation containing 3% by weight of silicon, 70% by weight choline hydrochloride and the rest water. According to formulation example A the neutralization can be carried out to a pH of 2.7-3.0. The bioavailability of the resulting stock solution is very high compared to other silicon compounds (silicates, clay, silica, horsetail, zeolites, . . . ), but those preparations are not stable after dilution.